“You can do things with a robot that the real-life creatures cannot do", says Wouter Halfwerk, associate professor at Vrije Universiteit Amsterdam, one of the researchers who led the research project. “For instance, you can investigate whether birds pay attention to movement when they learn their language, just as human babies watch lips so they can learn to talk more easily.” In the Seeing Voices project an international team of scientists led by Halfwerk and Katharina Riebel of Biology Leiden (IBL) developed and tested the robot in the Technology Centre of VU Amsterdam.
Vocal learning
“Just like children, young zebra finches start by babbling. They hear the songs of others of their species, remember them and start practising,” says Katharina Riebel. “Behavioural biologists want to find out more about this vocal learning, but up to now that has been done mainly by playing birdsong through a loudspeaker. But learning to sing involves a lot more, such as beak and throat movements, and posture. Zebra finches cannot learn as easily from a video recording as from another of their species.”
RoboFinch approved
Fortunately, the birds took to the RoboFinch as well. “Initially, zebra finches are generally wary of new objects, but they were enormously curious from the outset”, says PhD researcher Judith Varkevisser, who performed the experiments at Leiden University. “They come and sit on the perch alongside it and chirp to it. And even more importantly, the young birds sit quietly and study the RoboFinch when it begins to move and we play back birdsong. They genuinely seem to be listening to the robot! That proves that we can use the RoboFinch in our research into vocal learning and whether the movements associated with singing are important in that regard.”
Construction kit
With this positive result the Seeing Voices team can now compile a sort of kit made up of different aspects of birdsong. “Do we want movement only, audio only, or everything at the same time? We are also going to try to make the RoboFinch interactive. Then it can start singing as soon as the birds sit on a particular perch”, says Riebel.
Sharing to gain more knowledge
The results of the initial tests with six different RoboFinches have been published in Methods in Ecology and Evolution under an open-source licence, so everyone can 3D print and construct their own robot. “We are happy to share the blueprint with others in the hope that we be able to find out even more about vocal learning”, Wouter Halfwerk explains. “We really look forward to seeing what new insights we can obtain with this technique in the next few years.”
Read below how the RoboFinch was constructed
